I wanted a way to store my kitchen knives that would free up counter space and protect the knives' sharp edges from getting nicked and dulled (I spend enough time time sharpening my woodworking tools!).

If you're lucky to have a full shop like I do at Makeville Studio, you can start with rough lumber and mill to final size. Otherwise, start with 1x4 hardwood stock, available pre-milled from most home centers and lumber yards.

Crosscut lumber: Cut your milled lumber to size on the tablesaw: rip it to 4 in. and crosscut it to 24 in.. Or, crosscut 1x4 stock to 24 in. on a chopsaw or with a handsaw.
Tip: Before crosscutting, examine the board for defects such as checks (cracks running in from the ends), knots, and anything else you don't like the look of. Then look for areas with color and grain pattern that you do like. Your 24-in. length should exclude the "bad" stuff and include as much of the "good" as possible. A quick and handy tool for picking out the best area in a board is a simple homemade viewfinder like the one shown above.

Drilling

Lay out for the magnets: Lay out magnet locations on back of board. The 1/2-in.-dia. holes for the magnets will be spaced 1.5 in. apart, centered in the board.

Routing setup

Drill magnet holes: Load up the 1/2-in. Forstner bit in your drill press. Set the depth stop so that the center guide of the Forstner bit stops short of the front face of your board. You'll want the bottom of the hole to be at most 1/8 in. from the face of the board. Drill 15 holes.
Tip: No drill press? Use a handheld drill with an improvised depth stop, made of cardboard and tape.

Card scraping

Rout keyholes: Lay out and rout two keyhole mounting slots. Mark two 1.5-in. lines parallel to the long edge of the board, starting 1 in. from each side. Using a plunge router with an edge guide, plunge in about 1/2 in. and then rout out your 1.5-in. line.
Tip: No plunge router? Drill a 3/8-in. hole about 1/2 in. deep, place your stationary router in the hole, turn on the power, and rout the 1.5-in. straight line from there.

Inserting glue

Prep the surface for a finish: Prep the board for finishing. Use a card scraper or sanding block to remove any scratches or other marks from the visible face and edges of the board. The card scraper will give you a smooth finish very quickly. If you're sanding, start with 120-grit and then change to 220- or 240-grit for a final finish.
Tip: Soften sharp edges quickly using a block plane to create a light bevel (inset).

Applying finish

Install magnets: Glue in the magnets. One hole at a time, put a couple drops of cyanoacrylate (super) glue in the bottom of the hole and push in a magnet. Make sure the magnet is inserted fully. Tap it in gently with a dowel if necessary.

Finishing slurry

Finish the rack: Apply a mineral oil finish. This can be as simple as wiping on some oil, letting in soak in for 15 minutes, and then wiping it off. But if you want a buttery smooth finish, continue to the next step.

Sand in the finish: Load your sanding block with 400 grit wet-or-dry sandpaper and sand with the grain. When you see a thick oil/sawdust slurry forming, you're done sanding. Let the oil sit for 15 minutes and then wipe off.